Apparently extremely different opinions it seems
Although most says volume doesnt matter
Now the question is, what IS a water start?
It is the act of getting up on your board, and up foiling, right?
A few days ago I experienced being out really powered, maybe 8 knots with a 13 m2 LEI on long lines, on a 1200 cm2 big Surf wing, and a big area board 130 cm quite wide, so loads of power.
But nevertheless, when the wind dropped, maybe 5-6 knots max, I could still just manage to get on the board, but to absolutely no avail, as it would sink so deep that foiling was utterly impossible.
The kite even when sheeted out, tends to "hang" on the upturn, when looped, so no power here, and when it gets speed and more power, it can only help bring the board closer to the surface, but never up at speed, till the next "powerlull" all LEI kites got in low winds when looped, sinks the board again.
With a board with more volume, I would have been able to ride on the surface, and get ashore much faster this way even if the wind dropped further - but most likely I would have been able to pump the wing up foiling, maybe using a wave as they help immensely, especially when your board is free on the surface.
This wasnt even in marginal winds, but in "typical" kitefoiling winds - just a drop in wind like it happens quite often here in the winter (not so much in summer luckily)
Standing on the quite big but thin board and big wing, water over my waist, getting nowhere (@75 kg right now)
Even these waves didnt help at all later, when sunk so deep....
As seen here, it is not area that is lacking, but volume
The next day something similar happened, just with an 8 m2 kite and a shorter board in a lot more wind maybe 11-12 knots, sweetspot wind at first, but dropped, so board would sink no matter what, eventhough it would have been possible to foil with a bigger and floatier board, and at least get ashore a lot more comfortable instead of dragging in the cold winter water.
An 8 m2 gives you a lot of peak power when looped, so possible to get on the board, but as the power is lost during the loop also when only say 8-9 knots on normal lines, board wont come to the surface, and not a chance of getting up foiling
The day after, full power at first on the 118:
So this is why I say volume matters a lot, not only surface area eventhough it helps also of course...
Yes, you might just say I am a lousy rider, and maybe you are right about that - but I know for sure many are in this category, and many got wind that changes a lot
Of course, if there is loads of wind relative to your kite, so you can just dive or loop yourself into foiling in one dive or loop, volume doesnt matter, but that is evident and not the question, right?